Pallet flow rack, also known as “gravity flow,” “gravity flow pallet rack,” “flow through rack,” or simply “flow rack,” is a FIFO (first in, first out) warehouse storage system. The basic concept behind pallet flow rack is similar to that of a conveyor belt. Pallets are loaded at the back end of the rack system and gently “flow” down to the front of the lane at the opposite end. At the pick face, there is a stopping mechanism to keep the pallet from rolling off the front end. Each time a pallet is removed from the front of a lane, the pallets behind it move forward one position. This flow of inventory creates easy throughput for warehouses with a high volume of inventory movement.